Interplay of Rad51 with NF-κB pathway stimulates expression of HIV-1

PLoS One. 2014 May 21;9(5):e98304. doi: 10.1371/journal.pone.0098304. eCollection 2014.

Abstract

Transcription from the HIV-1 promoter is controlled by a series of ubiquitous and inducible cellular proteins with the ability to enter the nucleus and interact with the promoter. A DNA sequence spanning nucleotides -120 to -80, which supports the association of the inducible NF-κB transcription factor, has received much attention. Here we demonstrate that the interplay between Rad51, a key regulator of the homologous recombination pathway of DNA repair and whose level is induced upon HIV-1 infection, with the NF-κB pathway, augments transcription of the viral promoter. Evidently, stimulation of the NF-κB pathway by PMA and/or TSA promotes association of Rad51 with the LTR DNA sequence and that the p65 subunit of NF-κB is important for this event. Our results also demonstrate that, similar to p65, Rad51 utilizes the NF-κB pathway to position itself in the nucleus as ectopic expression of an IκB mutant impedes its nuclear appearance and transcriptional activity upon the HIV-1 LTR. Treatment of peripheral blood mononuclear cells with small molecules that inhibit Rad51 activity results in greater than 50% decrease in the HIV-1 infection of cells. These observations provide evidence for the involvement of DNA repair factors in control of HIV-1 gene activation and offer a new avenue for the development of anti-viral therapeutics that affect viral gene transcription in latently infected cells.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Astrocytes / cytology
  • Astrocytes / virology
  • Brain / embryology
  • Cell Nucleus / metabolism
  • Cells, Cultured
  • Gene Expression Regulation, Viral
  • HIV Infections / metabolism
  • HIV Long Terminal Repeat
  • HIV-1 / physiology*
  • Humans
  • Leukocytes, Mononuclear / cytology
  • Mutation
  • Promoter Regions, Genetic
  • Rad51 Recombinase / genetics
  • Rad51 Recombinase / metabolism*
  • Recombination, Genetic
  • Transcription Factor RelA / metabolism*
  • Transcriptional Activation

Substances

  • RELA protein, human
  • Transcription Factor RelA
  • RAD51 protein, human
  • Rad51 Recombinase